Here is a properly painted edge. This is my work. I used Fenice from Italy purchased at Tandy under their brand name Professional Leather Edge Paint . The leather is Horween Horse shoulder. The edges must be glued flush. Paint, let dry, lightly sand. Repeat using a higher grit sandpaper, repeat, repeat, repeat all the way to 1500 grit. Polish with paraffin wax.

I posted the link to his Instagram account. Here it is again: https://www.instagram.com/zj.handwork/
He's got all kinds of edge photographs - burnished, folded and some painted. Lots of photographs of his pricking irons too.
You can find the prices for his tools and wallets on his website.
http://purelyhandwork.ayh688.com/

ZJ hand stitches. He even sells pricking irons.
https://www.instagram.com/zj.handwork/
A lot of the Asian leathercrafters use dye, lots of sanding to very high grits and CMC, tokonole or wax to finish their edges. They paint some too.